1. Field of Invention
The present invention relates generally to mops and, more particularly, for example, to mops which are adapted to be used in dust and lint-free environments such as clean rooms.
2. Description of the Related Art
Clean rooms are rooms in which dust and other small particles are filtered from the air and in which low or non-linting clothing is worn to avoid contaminating such things as pharmaceuticals and electronic components and other delicate, sensitive equipment. The number of clean rooms has steadily increased in recent years due to the rapid growth in industries, such as the semi-conductor fabrication industry, which require clean rooms for manufacture and testing. As would be the case in any other facility, clean room floors must be periodically mopped. Mopping a clean room floor, however, presents a number of unique challenges. For example, the mop cannot itself produce lint, which is the case with ordinary string mops because the strings are made of cotton or other linting material. It is also important that the mop pick up very small dirt and dust particles.
One type of mop that is used in clean rooms includes string-like cleaning members formed from sheets of material having relatively long parallel strands or fibers, such as polyvinylalcohol ("PVA"). The long parallel fibers form capillaries or passageways which absorb cleaning solution and other liquids. Referring to FIG. 1, PVA cleaning element 10 includes a plurality of string-like cleaning members 12 and a base portion 14. The base portion and cleaning members are formed by cutting slits 16 into a sheet of PVA. A mop head is assembled by stacking a number of sheets (typically 10 to 15) one on top of the other and sewing them together. The mop head is folded along fold line 18 around an attachment rod on a bracket that secures the mop head to the mop. The cleaning members 12 will dangle from the attachment rod in a manner similar to the strings in a common string mop.
Mops having cleaning elements formed from materials such as PVA are an improvement over common string mops because they do not produce lint. However, the inventor herein has determined that there are a number of aspects of the mops of this type presently known in the art which may be improved. For example, the cleaning elements may tear at the intersection between the string-like cleaning members and at the free end of the cleaning members. Also, the manner in which the mop head is attached to the mop may be improved. The bracket having the attachment rod about which the mop head is folded, which is typically made of metal, defines the lateral edges of the mop. As a result, the bracket may scratch floors and other surfaces during cleaning. With respect to performance, the fibrous material on the top and bottom surfaces of PVA sheets (as well as sheets of similar materials) tends to absorb less liquid than the material beneath the surface. This may reduce the potential efficiency of the mop head.